Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 39
Filtrar
1.
FASEB J ; 34(6): 8082-8101, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32298026

RESUMO

Mammalian immune responses are initiated by "danger" signals--immutable molecular structures known as PAMPs. When detected by fixed, germline encoded receptors, pathogen-associated molecular pattern (PAMPs) subsequently inform the polarization of downstream adaptive responses depending upon identity and localization of the PAMP. Here, we report the existence of a completely novel "PAMP" that is not a molecular structure but an antigenic pattern. This pattern--the incidence of peptide epitopes with stretches of 100% sequence identity bound to both dendritic cell (DC) major histocompatibility (MHC) class I and MHC class II--strongly induces TH 1 immune polarization and activation of the cellular immune response. Inherent in the existence of this PAMP is the concomitant existence of a molecular sensor complex with the ability to scan and compare amino acid sequence identities of bound class I and II peptides. We provide substantial evidence implicating the multienzyme aminoacyl-tRNA synthetase (mARS) complex and its AIMp1 structural component as the key constituents of this complex. The results demonstrate a wholly novel mechanism by which T-helper (TH ) polarization is governed and provide critical information for the design of vaccination strategies intended to provoke cell-mediated immunity.


Assuntos
Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunidade Celular/imunologia , Peptídeos/imunologia , Sequência de Aminoácidos/fisiologia , Aminoacil-tRNA Sintetases/imunologia , Animais , Células Dendríticas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células Th1/imunologia
2.
Proc Natl Acad Sci U S A ; 114(25): 6498-6503, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28584129

RESUMO

Young researchers are crucially important for basic science as they make unexpected, fundamental discoveries. Since 1982, we find a steady drop in the number of grant-eligible basic-science faculty [principal investigators (PIs)] younger than 46. This fall occurred over a 32-y period when inflation-corrected congressional funds for NIH almost tripled. During this time, the PI success ratio (fraction of basic-science PIs who are R01 grantees) dropped for younger PIs (below 46) and increased for older PIs (above 55). This age-related bias seems to have caused the steady drop in the number of young basic-science PIs and could reduce future US discoveries in fundamental biomedical science. The NIH recognized this bias in its 2008 early-stage investigator (ESI) policy to fund young PIs at higher rates. We show this policy is working and recommend that it be enhanced by using better data. Together with the National Institute of General Medical Sciences (NIGMS) Maximizing Investigators' Research Award (MIRA) program to reward senior PIs with research time in exchange for less funding, this may reverse a decades-long trend of more money going to older PIs. To prepare young scientists for increased demand, additional resources should be devoted to transitional postdoctoral fellowships already offered by NIH.


Assuntos
Pesquisa Biomédica/economia , Pesquisadores/economia , Adulto , Docentes , Organização do Financiamento/economia , Humanos , Pessoa de Meia-Idade , National Institutes of Health (U.S.)/economia , Estados Unidos
3.
Infect Immun ; 85(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28674032

RESUMO

Chagas disease, caused by infection with the protozoan parasite Trypanosoma cruzi, is a leading cause of heart disease ("chagasic cardiomyopathy") in Latin America, disproportionately affecting people in resource-poor areas. The efficacy of currently approved pharmaceutical treatments is limited mainly to acute infection, and there are no effective treatments for the chronic phase of the disease. Preclinical models of Chagas disease have demonstrated that antigen-specific CD8+ gamma interferon (IFN-γ)-positive T-cell responses are essential for reducing parasite burdens, increasing survival, and decreasing cardiac pathology in both the acute and chronic phases of Chagas disease. In the present study, we developed a genetically adjuvanted, dendritic cell-based immunotherapeutic for acute Chagas disease in an attempt to delay or prevent the cardiac complications that eventually result from chronic T. cruzi infection. Dendritic cells transduced with the adjuvant, an adenoviral vector encoding a dominant negative isoform of Src homology region 2 domain-containing tyrosine phosphatase 1 (SHP-1) along with the T. cruzi Tc24 antigen and trans-sialidase antigen 1 (TSA1), induced significant numbers of antigen-specific CD8+ IFN-γ-positive cells following injection into BALB/c mice. A vaccine platform transduced with the adenoviral vector and loaded in tandem with the recombinant protein reduced parasite burdens by 76% to >99% in comparison to a variety of different controls and significantly reduced cardiac pathology in a BALB/c mouse model of live Chagas disease. Although no statistical differences in overall survival rates among cohorts were observed, the data suggest that immunotherapeutic strategies for the treatment of acute Chagas disease are feasible and that this approach may warrant further study.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Cardiomiopatia Chagásica/terapia , Imunoterapia/métodos , Vacinas/imunologia , Adenoviridae/genética , Animais , Antígenos de Protozoários/genética , Antígenos de Protozoários/imunologia , Cardiomiopatia Chagásica/prevenção & controle , Células Dendríticas/imunologia , Modelos Animais de Doenças , Portadores de Fármacos , Feminino , Vetores Genéticos , Interferon gama/metabolismo , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Transdução Genética , Resultado do Tratamento , Vacinas/administração & dosagem , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
4.
Cancer Immunol Immunother ; 66(10): 1345-1357, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28608115

RESUMO

This phase I trial reports the safety and activity of BPX101, a second-generation antigen-targeted autologous antigen presenting cell (APC) vaccine in men with metastatic castration-resistant prostate cancer (mCRPC). To manufacture BPX101, APCs collected in a single leukapheresis were transduced with adenoviral vector Ad5f35 encoding inducible human (ih)-CD40, followed by incubation with protein PA001, which contains the extracellular domain of human prostate-specific membrane antigen. The ih-CD40 represents a modified chimeric version of the dendritic cell (DC) co-stimulatory molecule, CD40, which responds to a bioinert membrane-permeable activating dimerizer drug, rimiducid (AP1903), permitting temporally controlled, lymphoid-localized, DC-specific activation. Eighteen men with progressive mCRPC following ≤1 prior chemotherapy regimen were enrolled to evaluate three doses of BPX101 (4 × 106, 12.5 × 106 and 25 × 106 cells) administered intradermally every 2-4 weeks followed by rimiducid (0.4 mg/kg) intravenous (IV) infusion 24 h after each BPX101 dose. There were no dose-limiting toxicities. Immune upregulation as well as anti-tumor activity was observed with PSA declines, objective tumor regressions and robust efficacy of post-trial therapy. This novel antigen-targeted and in vivo activated immunotherapy platform may warrant further development as monotherapy and as a component of rational combinations.


Assuntos
Antígenos CD40/metabolismo , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Neoplasias da Próstata/imunologia , Idoso , Vacinas Anticâncer/uso terapêutico , Estudos de Coortes , Humanos , Masculino
5.
J Urol ; 195(6): 1911-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26802582

RESUMO

PURPOSE: We used targeted mass spectrometry to study the metabolic fingerprint of urothelial cancer and determine whether the biochemical pathway analysis gene signature would have a predictive value in independent cohorts of patients with bladder cancer. MATERIALS AND METHODS: Pathologically evaluated, bladder derived tissues, including benign adjacent tissue from 14 patients and bladder cancer from 46, were analyzed by liquid chromatography based targeted mass spectrometry. Differential metabolites associated with tumor samples in comparison to benign tissue were identified by adjusting the p values for multiple testing at a false discovery rate threshold of 15%. Enrichment of pathways and processes associated with the metabolic signature were determined using the GO (Gene Ontology) Database and MSigDB (Molecular Signature Database). Integration of metabolite alterations with transcriptome data from TCGA (The Cancer Genome Atlas) was done to identify the molecular signature of 30 metabolic genes. Available outcome data from TCGA portal were used to determine the association with survival. RESULTS: We identified 145 metabolites, of which analysis revealed 31 differential metabolites when comparing benign and tumor tissue samples. Using the KEGG (Kyoto Encyclopedia of Genes and Genomes) Database we identified a total of 174 genes that correlated with the altered metabolic pathways involved. By integrating these genes with the transcriptomic data from the corresponding TCGA data set we identified a metabolic signature consisting of 30 genes. The signature was significant in its prediction of survival in 95 patients with a low signature score vs 282 with a high signature score (p = 0.0458). CONCLUSIONS: Targeted mass spectrometry of bladder cancer is highly sensitive for detecting metabolic alterations. Applying transcriptome data allows for integration into larger data sets and identification of relevant metabolic pathways in bladder cancer progression.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Metaboloma , Neoplasias da Bexiga Urinária/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/mortalidade , Estudos de Casos e Controles , Cromatografia Líquida , Humanos , Espectrometria de Massas , Metabolômica , Prognóstico , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/mortalidade
6.
Anticancer Drugs ; 25(8): 878-86, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24714082

RESUMO

As loss of DNA-repair proteins is common in urothelial carcinoma (UC), a rationale can be made to evaluate the activity of poly (ADP-ribose) polymerase (PARP) inhibitors to exploit synthetic lethality. We aimed to preclinically evaluate a PARP inhibitor, CEP-9722, and its active metabolite, CEP-8983, in UC. The activity of CEP-8983 was evaluated using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay against human UC cell lines. Flow cytometry, COMET assay, and western blot were performed to assess apoptosis, DNA damage, and DNA-repair proteins, respectively. RT4 xenografts received placebo or CEP-9722 (100 or 200 mg/kg/day) orally. Xenografts were subjected to immunohistochemistry for apoptosis [cleaved caspase (cc)-3] and angiogenesis (CD31). CEP-8983 (1 µmol/l) reduced the viability of RT4 and T24 cells by 20%, but did not reduce the viability of 5637 and TCC-SUP cells. Apoptosis and necrosis occurred in 9.7 and 9.1% of RT4 and 5637 cells, respectively. RT4 cells showed greater DNA damage compared with 5637 cells. Increased DNA damage occurred with combination versus CEP-8983 or cisplatin alone in RT4 and 5637 cells. T24 and RT4 showed the least RAD51 foci 8 h following radiation, whereas TCC-SUP and 5637 robustly induced RAD51 foci. CEP-9722 showed dose-dependent antitumor activity in RT4 xenografts; 200 mg/kg daily was better than control (P=0.04) and 100 mg/kg was not (P=0.26). Immunohistochemistry of xenografts showed a significant increase in cc-3 and decrease in CD31 with both doses (P<0.05). Biomarker-driven evaluation of PARP inhibitors in UC is justified as the activity of CEP-9722 correlated inversely with homologous recombination repair response to DNA damage.


Assuntos
Carbazóis/farmacologia , Dano ao DNA/efeitos dos fármacos , Ftalimidas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases , Pró-Fármacos/farmacologia , Reparo de DNA por Recombinação/efeitos dos fármacos , Neoplasias Urológicas/patologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Xenoenxertos , Humanos , Camundongos Nus , Necrose , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Neoplasias Urológicas/genética
7.
Nano Lett ; 13(12): 5832-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24195698

RESUMO

The optical diffraction limit imposes a bound on imaging resolution in classical optics. Over the last twenty years, many theoretical schemes have been presented for overcoming the diffraction barrier in optical imaging using quantum properties of light. Here, we demonstrate a quantum superresolution imaging method taking advantage of nonclassical light naturally produced in fluorescence microscopy due to photon antibunching, a fundamentally quantum phenomenon inhibiting simultaneous emission of multiple photons. Using a photon counting digital camera, we detect antibunching-induced second and third order intensity correlations and perform subdiffraction limited quantum imaging in a standard wide-field fluorescence microscope.


Assuntos
Microscopia/métodos , Nanotecnologia , Óptica e Fotônica , Luz , Fótons
8.
EMBO Rep ; 12(9): 971-9, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21799517

RESUMO

The activation of innate and adaptive immunity is always balanced by inhibitory signalling mechanisms to maintain tissue integrity. We have identified the E3 ligase c-Cbl--known for its roles in regulating lymphocyte signalling--as a modulator of dendritic cell activation. In c-Cbl-deficient dendritic cells, Toll-like receptor-induced expression of proinflammatory factors, such as interleukin-12, is increased, correlating with a greater potency of dendritic-cell-based vaccines against established tumours. This proinflammatory phenotype is accompanied by an increase in nuclear factor (NF)-κB activity. In addition, c-Cbl deficiency reduces both p50 and p105 levels, which have been shown to modulate the stimulatory function of NF-κB. Our data indicate that c-Cbl has a crucial, RING-domain-dependent role in regulating dendritic cell maturation, probably by facilitating the regulatory function of p105 and/or p50.


Assuntos
Células Dendríticas/imunologia , Subunidade p50 de NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-cbl/genética , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Animais , Antígenos Nucleares/biossíntese , Antígenos Nucleares/metabolismo , Proteínas Cromossômicas não Histona/biossíntese , Proteínas Cromossômicas não Histona/metabolismo , Células Dendríticas/metabolismo , Feminino , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/imunologia , Receptores Toll-Like/metabolismo
9.
J Immunol ; 186(7): 3934-45, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21357539

RESUMO

Dendritic cells (DCs) initiate proinflammatory or regulatory T cell responses, depending on their activation state. Despite extensive knowledge of DC-activating signals, the understanding of DC inhibitory signals is relatively limited. We show that Src homology region 2 domain-containing phosphatase-1 (SHP-1) is an important inhibitor of DC signaling, targeting multiple activation pathways. Downstream of TLR4, SHP-1 showed increased interaction with several proteins including IL-1R-associated kinase-4, and modulated LPS signaling by inhibiting NF-κB, AP-1, ERK, and JNK activity, while enhancing p38 activity. In addition, SHP-1 inhibited prosurvival signaling through AKT activation. Furthermore, SHP-1 inhibited CCR7 protein expression. Inhibiting SHP-1 in DCs enhanced proinflammatory cytokines, IL-6, IL-12, and IL-1ß production, promoted survival, and increased DC migration to draining lymph nodes. Administration of SHP-1-inhibited DCs in vivo induced expansion of Ag-specific cytotoxic T cells and inhibited Foxp3(+) regulatory T cell induction, resulting in an enhanced immune response against pre-established mouse melanoma and prostate tumors. Taken together, these data demonstrate that SHP-1 is an intrinsic global regulator of DC function, controlling many facets of T cell-mediated immune responses.


Assuntos
Células Dendríticas/enzimologia , Células Dendríticas/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Células Dendríticas/metabolismo , Células HEK293 , Humanos , Masculino , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição AP-1/metabolismo , Ativação Transcricional/imunologia
10.
Mol Ther ; 20(7): 1462-71, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22434138

RESUMO

Recent modest successes in ex vivo dendritic cell (DC) immunotherapy have motivated continued innovation in the area of DC manipulation and activation. Although ex vivo vaccine approaches continue to be proving grounds for new DC manipulation techniques, the intrinsic limits of ex vivo therapy, including high cost, minimal standardization, cumbersome delivery, and poor accessibility, incentivizes the development of vaccines compatible with in vivo DC targeting. We describe here a method to co-deliver both tumor-specific antigen (TSA) and an iMyD88/CD40 adjuvant (iMC), to DCs that combines toll-like receptor (TLR) and CD40 signaling. In this study, we demonstrate that simple TSA delivery via adenoviral vectors results in strong antitumor immunity. Addition of iMC delivered in a separate vector is insufficient to enhance this effect. However, when delivered simultaneously with TSA in a single bicistronic vector (BV), iMC is able to significantly enhance antigen-specific cytotoxic T-cell (CTL) responses and inhibit established tumor growth. This study demonstrates the spatial-temporal importance of concurrent DC activation and TSA presentation. Further, it demonstrates the feasibility of in vivo molecular enhancement of DCs necessary for effective antitumor immune responses.


Assuntos
Antígenos de Neoplasias/imunologia , Antígenos CD40/imunologia , Citotoxicidade Imunológica , Células Dendríticas/imunologia , Melanoma Experimental/terapia , Fator 88 de Diferenciação Mieloide/imunologia , Linfócitos T Citotóxicos/imunologia , Adjuvantes Imunológicos , Animais , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/genética , Antígenos CD40/metabolismo , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/metabolismo , Dependovirus , Feminino , Imunoterapia , Interleucina-12/metabolismo , Ativação Linfocitária , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/biossíntese
11.
Sci Transl Med ; 13(592)2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952672

RESUMO

In humans, the natural killer (NK) cell marker CD161 identifies several subsets of T cells, including a polyclonal CD8 αß T cell receptor-expressing subset with characteristic specificity for tissue-localized viruses. This subset also displays enhanced cytotoxic and memory phenotypes. Here, we characterized this unique T cell subset and determined its potential suitability for use in chimeric antigen receptor (CAR) T cell therapy. In mice, gene expression profiling among the CD161-equivalent CD8+ T cell populations (CD8+NK1.1+) revealed substantial up-regulation of granzymes, perforin, killer lectin-like receptors, and innate signaling molecules in comparison to CD8+NK1.1- T cells. Adoptive transfer of CD8+NK1.1+ cells from previously exposed animals offered substantially enhanced protection and improved survival against melanoma tumors and influenza infection compared to CD8+NK1.1- cells. Freshly isolated human CD8+CD61+ T cells exhibited heightened allogeneic killing activity in comparison to CD8+CD61- T cells or total peripheral blood mononuclear cells (PBMCs). To determine whether this subset might improve the antitumor efficacy of CAR T cell therapy against solid tumors, we compared bulk PBMCs, CD8+CD161-, and CD8+CD161+ T cells transduced with a human epidermal growth factor receptor-2 (HER2)-specific CAR construct. In vitro, CD8+CD161+ CAR-transduced T cells killed HER2+ targets faster and with greater efficiency. Similarly, these cells mediated enhanced in vivo antitumor efficacy in xenograft models of HER2+ pancreatic ductal adenocarcinoma, exhibiting elevated expression of granzymes and reduced expression of exhaustion markers. These data suggest that this T cell subset presents an opportunity to improve CAR T cell therapy for the treatment of solid tumors.


Assuntos
Adenocarcinoma , Memória Imunológica , Animais , Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Camundongos , Subpopulações de Linfócitos T
12.
Opt Express ; 18(22): 22693-701, 2010 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-21164608

RESUMO

We present a simple and easily implementable scheme for multiplexed Coherent Anti-Stokes Raman Scattering (CARS) spectroscopy and microscopy using a single femtosecond pulse, shaped with a narrow spectral notch. We show that a tunable spectral notch, shaped by a resonant photonic crystal slab, can serve as a narrowband, optimally time-delayed probe, resolving a broad vibrational spectrum with high spectral resolution in a single-shot measurement. Our single-source, single-beam scheme allows the simple transformation of any multiphoton microscope with adequate bandwidth into a nearly alignment-free CARS microscope.

13.
Front Immunol ; 11: 613204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33597948

RESUMO

NK1.1 and its human homolog CD161 are expressed on NK cells, subsets of CD4+ and CD8+ T cells, and NKT cells. While the expression of NK1.1 is thought to be inhibitory to NK cell function, it is reported to play both costimulatory and coinhibitory roles in T-cells. CD161 has been extensively studied and characterized on subsets of T-cells that are MR1-restricted, IL-17 producing CD4+ (TH17 MAIT cells) and CD8+ T cells (Tc17 cells). Non-MAIT, MR1-independent CD161-expressing T-cells also exist and are characterized as generally effector memory cells with a stem cell like phenotype. Gene expression analysis of this enigmatic subset indicates a significant enhancement in the expression of cytotoxic granzyme molecules and innate like stress receptors in CD8+NK1.1+/CD8+CD161+ cells in comparison to CD8+ cells that do not express NK1.1 or CD161. First identified and studied in the context of viral infection, the role of CD8+CD161+ T-cells, especially in the context of tumor immunology, is still poorly understood. In this review, the functional characteristics of the CD161-expressing CD8+ T cell subset with respect to gene expression profile, cytotoxicity, and tissue homing properties are discussed, and application of this subset to immune responses against infectious disease and cancer is considered.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Receptores de IgG/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Humanos , Células Matadoras Naturais/imunologia
14.
Front Immunol ; 11: 608024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33384695

RESUMO

The immune response consists of a finely-tuned program, the activation of which must be coupled with inhibitory mechanisms whenever initiated. This ensures tight control of beneficial anti-pathogen and anti-tumor responses while preserving tissue integrity, promoting tissue repair, and safeguarding against autoimmunity. A cogent example of this binary response is in the mobilization of co-stimulatory and co-inhibitory signaling in regulating the strength and type of a T-cell response. Of particular importance is the costimulatory molecule CD28 which is countered by CTLA-4. While the role of CD28 in the immune response has been thoroughly elucidated, many aspects of CTLA-4 biology remain controversial. The expression of CD28 is largely constrained to constitutive expression in T-cells and as such, teasing out its function has been somewhat simplified by a limited and specific expression profile. The expression of CTLA-4, on the other hand, while reported predominantly in T-cells, has also been described on a diverse repertoire of cells within both lymphoid and myeloid lineages as well as on the surface of tumors. Nonetheless, the function of CTLA-4 has been mostly described within the context of T-cell biology. The focus on T-cell biology may be a direct result of the high degree of amino acid sequence homology and the co-expression pattern of CD28 and CTLA-4, which initially led to the discovery of CTLA-4 as a counter receptor to CD28 (for which a T-cell-activating role had already been described). Furthermore, observations of the outsized role of CTLA-4 in Treg-mediated immune suppression and the striking phenotype of T-cell hyperproliferation and resultant disease in CTLA-4-/- mice contribute to an appropriate T-cell-centric focus in the study of CTLA-4. Complete elucidation of CTLA-4 biology, however, may require a more nuanced understanding of its role in a context other than that of T-cells. This makes particular sense in light of the remarkable, yet limited utility of anti-CTLA-4 antibodies in the treatment of cancers and of CTLA-4-Ig in autoimmune disorders like rheumatoid arthritis. By fully deducing the biology of CTLA-4-regulated immune homeostasis, bottlenecks that hinder the widespread applicability of CTLA-4-based immunotherapies can be resolved.


Assuntos
Antígeno CTLA-4/metabolismo , Sistema Imunitário/metabolismo , Linfócitos T/metabolismo , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Antígeno CTLA-4/genética , Regulação da Expressão Gênica , Humanos , Sistema Imunitário/imunologia , Neoplasias/imunologia , Neoplasias/metabolismo , Transdução de Sinais , Linfócitos T/imunologia
15.
Int J Cancer ; 122(2): 363-71, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17935126

RESUMO

Cellular transformation is associated with a number of phenotypic, cell biological, biochemical and metabolic alterations. The detection and classification of morphological cellular abnormalities represents the foundation of classical histopathology and remains an important mainstay in the clinic. More recently, significant effort is being expended towards the development of noninvasive modalities for the detection of cancer at an early stage, when therapeutic interventions are highly successful. Methods that rely on the detection of optical signatures represent one class of such approaches that have yielded promising results. In our study, we have applied two spectroscopic imaging approaches to systematically identify in a quantitative manner the fluorescence and light scattering signatures of subcellular abnormalities that are associated with cellular transformation. Notably, we find that tryptophan images reveal not only intensity but also localization differences between normal and human papillomavirus immortalized cells, possibly originating from changes in the expression, 3D packing and organization of proteins and protein-rich subcellular organelles. Additionally, we detect alterations in cellular metabolism through quantitative evaluation of the NADH, FAD fluorescence and the corresponding redox ratio. Finally, we use light scattering spectroscopy to identify differences in nuclear morphology and subcellular organization that occur from the nanometer to the micrometer scale. Thus, these optical approaches provide complementary biomarkers based on endogenous fluorescence and scattering cellular changes that occur at the molecular, biochemical and morphological level. Since they obviate the need for staining and tissue removal and can be easily combined, they provide desirable options for further clinical development and assessment.


Assuntos
Biomarcadores Tumorais/metabolismo , Células Epiteliais/virologia , Papillomaviridae/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Células Cultivadas , Feminino , Humanos , Imageamento Tridimensional , Luz , Microscopia de Fluorescência , Oxirredução , Espalhamento de Radiação , Espectrometria de Fluorescência , Neoplasias do Colo do Útero/virologia
16.
J Urol ; 179(4): 1243-56, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18280515

RESUMO

PURPOSE: Clinical benign prostatic hyperplasia is primarily diagnosed based on a diverse array of progressive lower urinary tract symptoms and is likely distinct from histological benign prostatic hyperplasia, which is detected by the presence of nonmalignant proliferation of prostate cells but may or may not be associated with symptoms. Pharmacological management of lower urinary tract symptoms has emerged as an effective initial treatment for clinical benign prostatic hyperplasia due to the introduction of new drug therapies shown to be effective in recent large clinical trials. Despite advances in symptom management and research into disease pathology, diagnostic strategies for the prediction of benign prostatic hyperplasia progression and response to drug modalities are lacking, and questions remain as to the molecular differences underlying clinical (symptomatic) vs histological (nonsymptomatic) benign prostatic hyperplasia. MATERIALS AND METHODS: As part of the Medical Therapy of Prostatic Symptoms (MTOPS) clinical trial, which demonstrated the effectiveness of combination drug therapy in slowing benign prostatic hyperplasia progression, an archive of biological specimens linked to clinical data was collected for future profiling of disease pathology and changes associated with response to drug therapy. The MTOPS Prostatic Samples Analysis (MPSA) Consortium was established to identify and validate molecular markers that may better define benign prostatic hyperplasia related pathologies, identify risk of progression of lower urinary tract symptoms, and predict response to drug therapy using the MTOPS archive. The cooperating MPSA Biomarker Discovery Sites and Pathology Coordinating Center use diverse methodologies and scientific approaches as well as unique expertise to address the goals of the Consortium. RESULTS: To date the MPSA has identified a number of promising biomarkers as well as other molecular and cellular changes associated with benign prostatic hyperplasia. CONCLUSIONS: These findings and ongoing Consortium discovery efforts have the potential to provide a greater understanding of the defects underlying disease pathology, and may lead to the development of early and more effective pharmacological treatment strategies for benign prostatic hyperplasia.


Assuntos
Hiperplasia Prostática/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/sangue , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/genética
17.
Biomaterials ; 29(15): 2359-69, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18313137

RESUMO

Current approaches to study biomaterial mineralization are invasive and prevent dynamic characterization of this process within the same sample. Polarized light scattering spectroscopy (LSS) may offer a non-invasive alternative for assessing the levels of mineralization as well as some aspects of the organization of the mineral deposits. Specifically, we used LSS to characterize the formation of hydroxyapatite deposits on three types of silk films (water-annealed, methanol-treated and polyaspartic acid (PAA)-mixed) following 1, 3, 5 and 7 cycles of mineralization. We found that the total light scattering intensity provided a quantitative measure of the degree of mineralization as confirmed by thermal gravimetric analysis (TGA). The PAA-mixed silk films yielded the highest level of mineral deposition and the water-annealed ones the least, consistent with the beta sheet content of the films prior to the onset of mineralization. The wavelength dependence of the singly backscattered light was consistent with a self-affine fractal morphology of the deposited films within scales in the range of 150-300nm; this was confirmed by Fourier analysis of scanning electron microscopy (SEM) images of the corresponding films. The deposits of minerals in the water-annealed films were predominantly flake-like, with positively correlated density fluctuations (Hurst parameter, H>0.5), whereas methanol-treated and PAA-mixed silk films resulted in densely-packed, bulk mineral deposits with negatively correlated density fluctuations (H<0.5). Therefore, LSS could serve as a valuable tool for understanding the role of biomaterial properties in mineral formation, and, ultimately, for optimizing biomaterial designs that yield mineral deposits with the desired organization.


Assuntos
Materiais Biocompatíveis/química , Calcificação Fisiológica , Luz , Espalhamento de Radiação , Engenharia Tecidual/métodos , Materiais Biocompatíveis/metabolismo , Cloreto de Cálcio/química , Varredura Diferencial de Calorimetria/métodos , Cristalização , Fibroínas/química , Fibroínas/metabolismo , Fibroínas/ultraestrutura , Análise de Fourier , Fractais , Metanol/química , Microscopia Eletrônica de Varredura , Peptídeos/química , Estrutura Secundária de Proteína , Análise Espectral/métodos , Termogravimetria
18.
Curr Urol Rep ; 8(4): 269-74, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18519010

RESUMO

Benign prostatic hyperplasia (BPH) is the most common urologic affliction in aging men, leading to adverse clinical outcomes in a significant proportion of the population. Serum prostate-specific antigen (PSA) has been established as a marker for prostate cancer for the past two decades but more recently has been recognized as an equally important marker of BPH presence and progression. Over this time, the discovery and study of multiple isoforms of PSA have led to even more sensitive and specific methods to differentiate BPH from prostate cancer. Herein we review the expression, processing, and biochemistry of PSA and its derivatives and discuss the potential of these isoforms, both individually and in combination, to serve as determinants of BPH severity and progression.


Assuntos
Antígeno Prostático Específico/sangue , Hiperplasia Prostática/sangue , Biomarcadores/sangue , Progressão da Doença , Humanos , Masculino , Valor Preditivo dos Testes , Isoformas de Proteínas/sangue
19.
Nat Hum Behav ; 6(10): 1324-1326, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36109653
20.
Front Immunol ; 8: 1801, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29379495

RESUMO

Dendritic cells (DCs) must integrate a broad array of environmental cues to exact control over downstream immune responses including TH polarization. The multienzyme aminoacyl-tRNA synthetase complex component AIMp1/p43 responds to cellular stress and exerts pro-inflammatory functions; however, a role for DC-expressed AIMp1 in TH polarization has not previously been shown. Here, we demonstrate that the absence of AIMp1 in bone marrow-derived DC (BMDC) significantly impairs cytokine and costimulatory molecule expression, p38 MAPK signaling, and TH1 polarization of cocultured T-cells while significantly dysregulating immune-related gene expression. These deficits resulted in significantly compromised BMDC vaccine-mediated protection against melanoma. AIMp1 within the host was also critical for innate and adaptive antiviral immunity against influenza virus infection in vivo. Cancer patients with AIMp1 expression levels in the highest tertiles exhibited a 70% survival advantage at 15-year postdiagnosis as determined by bioinformatics analysis of nearly 9,000 primary human tumor samples in The Cancer Genome Atlas database. These data establish the importance of AIMp1 for the effective governance of antitumor and antiviral immune responses.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA